The prior art teaches that archery arrows of aluminum construction are expensive, and as such, has resulted in making the replaceability of the arrowheads an attractive feature in arrow design. Typically, arrowheads are designed for removal from the arrow shafts by means of providing the arrowheads with a threaded shaft which is threadedly secured within an insert provided at the leading end of the arrow shaft, see generally U.S. Pat. No. 2,212,345, teaching an arrowhead threadedly secured to a shaft and also teaching an arrowhead having blades (broadhead) arranged in a spiral manner about the arrow's shank to induce arrow spin. The broadhead arrowhead has evolved to arrowhead designs which include a nose arrow tip portion followed by a broadhead bladed portion, see generally U.S. Pat. No. 4,565,377 teaching also to provide an arrow tip with a partial recessed area to improve penetration of the target. The broadhead arrow, when provided with a separate arrow tip member, has further been designed with structure which allows rotation of the broadhead portion separate from the arrow tip and fletched arrow shaft, see generally U.S. Pat. Nos. 4,175,749 and 4,534,568. The foregoing prior art has also taught to coordinate the pitch of the broadhead blades with the pitch of the fletching to effect improved in-flight characteristics.
However, the foregoing prior art has not taught to provide a combined arrow tip and broadhead portion structure in a broadhead arrow that will prolong rotation of the arrow during penetration of the target, that is, structure that will encourage continuing rotation during penetration into the target.
Thus, a need is seen to exist to further improve the rotational freedom of the broadhead portion, to not only effect improvement of in-flight characteristics, but to also improve and prolong rotation of the broadhead arrow structure during penetration of the target.
Further, a need is further seen to exist to provide an improved arrow tip structure along with improved broadhead blade structure that will jointly effect the above desired prolong rotation and improved penetration into the target, especially hard bone material encountered in hunting large animals.